This invention relates in general to routing information packets in a network and more specifically to routing packets via network address translators.
Companies that provide Internet access and resources to subscribers are referred to as Internet Service Providers (ISPs). One resource with which an ISP is concerned is the overall bandwidth capability of the facilities (e.g., routers, switches, servers, bridges, backbones, etc.) that are under the ISP's control. Management and control of traffic that uses the ISP's bandwidth can be critical to the ISP's successful operation.
Some popular uses of the Internet such as Voice over Internet Protocol (VoIP), video, streaming content, etc., require large amounts of bandwidth and are also becoming increasingly popular. These uses can utilize facilities and resources owned and/or operated by unrelated entities. Often, if an entity such as an ISP is committed to open and versatile support of Internet services, the entity may not have sufficient ability to manage or control traffic through its facilities, such as by redirecting traffic for load balancing or other purposes.
Typically, traffic over the Internet and other networks is directed according to sender and receiver Internet Protocol (IP) addresses and port numbers. However, computers on private networks such as a local area network (LAN) are usually not assigned registered IP addresses, and therefore cannot communicate directly with computers on a public network such as the Internet. One of the ways in which communication can take place in this case is by means of Network Address Translators (NATs). NATs are assigned a set of registered IP addresses, which are translated to IP addresses of computers on the private network. These registered IP addresses are then used by the NAT to allow communication between the computers on the private network and computers on the public network. In addition, an entire network of computers on a private network can be assigned a single IP address by a NAT.
An important application of the NAT is with IP telephony such as VoIP. VoIP calls made from private networks can be routed to public networks through the NAT, making communication faster and more reliable. Different types of NATs include full-cone NATs, restricted-cone NATs and port-restricted cone NATs. An ISP usually configures NATs to perform different types of address mappings. Depending on the type of traffic and the NAT configuration there may be such increased use of facilities and resources that serious adverse effects such as overloading and failure can occur. This may result in users experiencing a slowdown or stopping of network response.
Accordingly, there is a need for a method and system that provides management of network traffic.